Temperature determination and control of exhaust aftertreatment system adsorbers

Abstract

One embodiment is a unique method including determining a temperature of a NOx adsorber. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.

1. A method comprising:
 receiving information of a first temperature sensor, a second temperature sensor, a first oxygen sensor, and a second oxygen sensor; and 
 calculating a temperature of a NOx adsorber based upon the information of the first temperature sensor, the second temperature sensor, the first oxygen sensor, and the second oxygen sensor according to a first set of operations or according to a second set of operations; 
 wherein the calculating is further based upon a catalyst trim fuel value. 
 
     
     
       2. A method according to  claim 1  wherein the first temperature sensor is an adsorber inlet temperature sensor, the second temperature sensor is an adsorber outlet temperature sensor, the first oxygen sensor is an adsorber inlet oxygen sensor, and the second oxygen sensor is an adsorber outlet oxygen sensor. 
     
     
       3. A method according to  claim 1  further comprising receiving engine speed information; wherein the calculating is further based upon the engine speed information. 
     
     
       4. A method according to  claim 1  further comprising receiving fresh air flow information; wherein the calculating is further based upon the fresh air flow information. 
     
     
       5. A method according to  claim 1  wherein the catalyst trim fuel value includes information of two or more fuel injection pulses. 
     
     
       6. A method according to  claim 1  wherein the catalyst trim fuel value includes a pulse at greater than about 90 degrees after top dead center. 
     
     
       7. A method according to  claim 1  wherein the catalyst trim fuel value includes a first pulse and a second pulse, the first pulse being greater than about 60 degrees after top dead center, the second pulse being greater than the first pulse. 
     
     
       8. A method according to  claim 6  including a main injection pulse, a pilot injection pulse, a first post injection pulse, a second post injection pulse, and a third post injection pulse. 
     
     
       9. A method according to  claim 1  further comprising initiating adsorber regeneration based upon the calculating; wherein the regeneration is accomplished using in cylinder fueling commands. 
     
     
       10. A system comprising:
 a processor; 
 a diesel exhaust aftertreatment subsystem including an adsorber; and 
 a sensor subsystem including a temperature sensor arrangement operable to provide sensed temperature information for two locations, an oxygen sensor arrangement operable to provide sensed oxygen information for two locations; wherein 
 the processor processes the sensed temperature information and the sensed oxygen information to determine an adsorber temperature and generates fueling commands based upon the adsorber temperature effective to regenerate the adsorber. 
 
     
     
       11. A system according to  claim 10  wherein the processor is a component of an engine control unit. 
     
     
       12. A system according to  claim 10  wherein the diesel exhaust aftertreatment subsystem includes a diesel oxidation catalyst and a diesel particulate filter. 
     
     
       13. A system according to  claim 10  wherein the temperature sensor arrangement includes a first sensor positioned to sense an inlet temperature of the adsorber and a second sensor positioned to sense an outlet temperature of the adsorber. 
     
     
       14. A system according to  claim 10  wherein the oxygen sensor arrangement includes a first sensor positioned to sense adsorber inlet information and a second sensor positioned to sense an adsorber outlet information. 
     
     
       15. A system according to  claim 10  wherein the processor calculates first and second fuel injection values to determine the adsorber temperature. 
     
     
       16. A system according to  claim 10  wherein the processor processes fresh air flow information to determine the adsorber temperature. 
     
     
       17. A system according to  claim 10  wherein the processor is operable in a second mode in which the adsorber temperature is determined based upon a second temperature model. 
     
     
       18. A system according to  claim 10  further comprising means for controlling fueling based upon the adsorber temperature. 
     
     
       19. A system according to  claim 10  further comprising means for maintaining the adsorber temperature within one or more limits. 
     
     
       20. One or more non-transitory computer readable media configured with computer executable instructions comprising:
 first instructions to determine an adsorber temperature based upon an adsorber temperature value, an adsorber lambda value, a fueling value, a fresh air flow value, and an engine speed value; and 
 second instructions to determine an adsorber temperature based upon an alternate logic; 
 wherein the alternate logic includes a filter which filters input catalyst trim fuel information. 
 
     
     
       21. One or more computer readable media according to  claim 20  wherein the first instructions to determine an adsorber temperature are further based upon a second adsorber temperature value. 
     
     
       22. One or more computer readable media according to  claim 20  wherein the first instructions to determine an adsorber temperature are further based upon a second adsorber lambda value. 
     
     
       23. One or more computer readable media according to  claim 20  wherein the first instructions to determine an adsorber temperature are further based upon a second fueling value. 
     
     
       24. One or more computer readable media according to  claim 20  wherein the second instructions include a first operator that multiplies a first NOx adsorber inlet temperature variable and a second variable and provides a first output, a second operator that sums the first output and a third variable and provides a second output, a third operator that divides the second output by a fourth variable and provides a third output, and a filter that filters the third output and outputs to a fifth variable which is provided to an output block. 
     
     
       25. One or more computer readable media according to  claim 20  wherein the alternate logic processes information an adsorber inlet temperature and an adsorber outlet temperature through two distinct functions. 
     
     
       26. One or more computer readable media according to  claim 20  wherein the media are operatively coupled with an ECU. 
     
     
       27. One or more computer readable media according to  claim 26  wherein the ECU is operatively coupled with a diesel engine. 
     
     
       28. One or more computer readable media according to  claim 27  wherein the diesel engine is operatively coupled with a vehicle.